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Globally
8th Mar 2006, 17:18
Who sets the Mode control panel (MCP) altitude in your "glass cockpit" airplane with the autopilot engaged - the pilot flying (PF), or the pilot not flying (PNF)? Currently, our airline procedures call for the PF to set new altitudes on the MCP when the autopilot is engaged. When the PF is manually flying the airplane, then the PNF sets the MCP altitude. There is some discussion in our airline that maybe improved CRM would result if the PNF makes all MCP altitude selections in both manual and autoflight. Can anyone shed any light on which procedure has the better history of safety?
In addition, if the PNF makes all MCP altitude selections, then who actually pushes the MCP altitude selector to make the airplane descend or climb, as in a VNAV situation? How do both pilots coordinate the correct altitude is set in the window? Many thanks for your ideas/discussion.

Empty Cruise
8th Mar 2006, 17:32
My guess would be along these lines: when AP not in, PM sets the MCP altitude only out of convenience, since PF is busy flying. When the AP is in, PF sets the MCP while PM still handles the radios, i.e. reads the clearance back.

If your PM both handles the radios and sets the MCP, chances are that a misunderstanding in cleared altitude will not be picked up so easily, e.g. if ATC goes "ABC123, climb to FL310", PM misunderstands and reads back "Climb FL210, ABC123", if PF has heard the clearance correctly, he will now read back "Climb FL310" and point to his newly selected MCP altitude. The idea is that PM will then query this, along the lines "I just read 210 back" etc. etc. and the problem gets solved.

If PF is left out of the MCP loop, there is a danger that he/she will drop out of the RT loop, since PM "takes care of it all".

Anyway, PF is charged with lateral and vertical navigation of the aircraft per most SOPs, so setting an altitude constraint should logically belong with the PF.

Just a thought - have no idea weather research into closed-loop-comms can verify or falsify my little theory :}

Empty

BOAC
8th Mar 2006, 17:32
Quite honestly, a/p in, it matters not a jot WHO does it as long as it is 'verbalised' as they say and cross-checked. It does, however, make sense IMO for HP to 'fly' the a/pilot - ie press the button, but if he/she is eating a delicious crew meal at the time..........................

haughtney1
8th Mar 2006, 20:08
Define mutual exclusivity....delicious and crewfood :}

sorry thread creep...........

captjns
8th Mar 2006, 20:20
The SOPs for all airlines with glass cockpits I flew with for the past 17 years was:

A/P engaged: Flying Pilot sated altitude/FL, sets altitude and points to it until the non flying pilot points to the selected altitude and confirms it verbally.

A/P not engaged: Flying Pilot states "Set Alt/FL" Nonflying Pilot sets altitude and states "ALT/FL set" and points to it until the flying confirms it verbally.

Same rule applies to older jurassic typ steam driven gaged equipped jets.

ElNino
9th Mar 2006, 13:06
In my company with its ancient very much non-glass 146's, we do as follows:

AP engaged: HP selects cleared altitude/FL in window, presses the ALT ARM button, states "FL***/** thousand feet set and armed" and leaves his finger by the window until MP replies "checked"

AP disengaged: same phraseology but MP does the setting and HP checks it.

We used to have the MP always doing the selecting, regardless of AP in or out, but most people find it far more sensible to have the HP doing all the button pressing when the AP is engaged.
I also think it's safer as it's very easy to inadvertently disarm the selected altitude on the 146, which, when it happened, led to both pilots simultaneously playing with the MCP, just as the aircraft was continuing through the cleared altitude. Not for no reason does the 146 have a history of alt busts!

PRNAV1
11th Mar 2006, 20:51
Pretty much the same story with us.

A/P off- PF asks for changes once given by ATC and PM sets them on the MCP (airbus-FCU)
A/P engaged- PF deals with the changes on the MCP.

BizJetJock
11th Mar 2006, 21:07
Interesting one. As a freelance I fly the same type for several operators, and all but one have the NHP set the altitude regardless of AP status. All other selections are by the HP if AP engaged and NHP if not. So, apart from the brainache of having to remember which SOP's to follow, I find that there is very little problem doing either method. There is certainly no difference in the level of awareness - in either system if both guys are paying attention there is plenty of cross checking, and if someone is just paying lip service rather than thinking then things can be missed.
I do personally prefer the NHP setting the alt, as you can find you run out of fingers if ATC give you a heading and altitude at the same time - Set heading, change to heading mode, set altitude (arm alt select in older ones), select vertical mode, select speed and/or VS - I think I need a lie down after that.:eek:

Kent BeTrue
17th Mar 2006, 15:09
While there has been some agreement who sets the MCP at which point, the most glaring part of this discussion has been whether the PF or HP is flying with a PNF or a PM or a NHP or a RO or....
Maybe this terminology could be discussed as to which is the most useful / accurate / pc etc
Cheers

Ricky Whizz
9th Apr 2006, 09:30
Surely with A/P engaged logic would dictate that selections on the MCP should normally be done by the Handling Pilot/Pilot Flying or whatever else you want to call him/her.

Otherwise he/she ain't handling or flying anything!!!!

SixDelta
20th Apr 2006, 13:14
We've just gone through this in my company. The SOP's call for PF to set it with the AP engaged and PNF to set it when the jet is being "hand flown".

My own preference is to have PNF set it immediately after the readback to ATC with the PF then comfirming it verbally regardless of whether the AP's "in" or not. I have found, ocassionally, the other way round can lead to the cross-check / confirmation being missed.

6D

aviator
24th Apr 2006, 03:34
PNF (Pilot Not Flying) always

mwaugh
26th Apr 2006, 11:49
A/P off - PNF handles the FCP, all modes including altitude set.
A/P on - PF handles the FCP - all modes including altitude set.

I guess I could see doing it differently, but this just feels right to me.

World of Tweed
29th Apr 2006, 12:29
If flying with A/P in CMD then PF sets the MCP.....Penne Bolagnese not withstanding.

If Manually flying the PNF sets the MCP